<template>
  <div class="article-container">
    <!-- 导航栏 -->
    <van-nav-bar
      class="page-nav-bar"
      title="黑马头条"
      @click-left="$router.back()"
      left-arrow>
    </van-nav-bar>
    <!-- 导航栏 -->

    <!-- 加载中 -->
      <div class="loading-wrap" v-if="loading">
        <van-loading
          color="#3296fa"
          vertical
        >加载中</van-loading>
      </div>
    <!-- /加载中 -->

    <!-- 加载完成文章详情 -->
      <div class="article-detail" v-else-if="article.title">
        <!-- 文章标题 -->
        <h1 class="article-title">{{ article.title }}</h1>
        <!-- 文章标题 -->
        <!-- 用户信息 -->
        <van-cell class="user-info" center :border="false">
          <!-- 头像 -->
          <van-image
            class="avatar"
            slot="icon"
            round
            fit="cover"
            :src="article.aut_photo"
          />
          <div slot="title" class="user-name">{{ article.aut_name }}</div>
          <div slot="label" class="publish-date">{{ article.pubdate | relativeTime }}</div>
           <follow-user
           class="follow-btn"
           v-model="article.is_followed"
           :user-id="article.aut_id">
           </follow-user>
        </van-cell>
        <!-- 用户信息 -->

        <!-- 文章内容 -->
        <div
        class="article-content markdown-body"
        v-html="article.content"
        ref="article-content"></div>
        <van-divider>正文结束</van-divider>
        <!-- 文章内容 -->
        <!-- 评论区域 -->
        <comment-list
        :source="article.art_id"
        :list="commentList"
        @onload-success="totalCommentCount = $event.total_count"
        :article-id="article.art_id"
        @reply-click="onReplyClick"/>
        <!-- 评论区域 -->
         <!-- 底部区域 -->
        <div class="article-bottom">
          <van-button
          class="comment-btn"
          type="default"
          round
          size="small"
          @click="isPostShow=true">写评论
          </van-button>
          <van-icon class="comment-icon" name="comment-o" :badge="totalCommentCount" />
          <collect-article
          class="btn-item"
          :article-id="article.art_id"
          v-model="article.is_collected"/>
          <like-article
          class="btn-item"
          v-model="article.attitude"
          :article-id="article.art_id"/>
          <van-icon name="share" color="#777777"></van-icon>
        </div>
        <!-- 底部区域 -->
        <!-- 发表评论 -->
        <van-popup
          v-model="isPostShow"
          position="bottom">
          <comment-post :target="article.art_id"
          @post-success="onPostSuccess"/>
        </van-popup>
         <!-- 发表评论 -->
      </div>
    <!-- 加载完成文章详情 -->

    <!-- 加载失败404 -->
      <div class="error-wrap" v-else-if="errStatus === 404">
          <van-icon name="failure" />
          <p class="text">该资源不存在或已删除！</p>
      </div>
    <!-- 加载失败404 -->

    <!-- 加载失败：其它未知错误（例如网络原因或服务端异常） -->
      <div class="error-wrap" v-else>
          <van-icon name="failure" />
          <p class="text">内容加载失败！</p>
          <van-button class="retry-btn" @click="loadArticle">点击重试</van-button>
      </div>
    <!-- 加载失败：其它未知错误（例如网络原因或服务端异常） -->
    <!-- 评论回复 -->
      <van-popup
        v-model="isReplyShow"
        get-container="body"
        round
        position="bottom"
        :style="{ height: '90%' }">
        <comment-reply
        :comment="currentComment"
        @close="isReplyShow = false"
        v-if="isReplyShow"/>
      </van-popup>
    <!-- /评论回复 -->

  </div>
</template>

<script>
import { getArticleById } from '@/api/article'
import { ImagePreview } from 'vant'
// import { addFollow, deleteFollow } from '@/api/user'
import FollowUser from '@/components/follow-user'
// 收藏
import CollectArticle from '@/components/collect-article'
// 点赞
import LikeArticle from '@/components/like-article'
// 评论
import CommentList from './components/comment-list'
// 写评论
import CommentPost from './components/comment-post'
// 评论回复
import CommentReply from './components/comment-reply'
export default {
  // 组件名称
  name: 'article-container',
  provide: function () {
    return {
      articleId: this.articleId
    }
  },
  // 局部注册的组件
  components: {
    FollowUser,
    CollectArticle,
    LikeArticle,
    CommentList,
    CommentPost,
    CommentReply
  },
  // 组件参数 接收来自父组件的数据
  props: {
    articleId: {
      type: [Number, String, Object],
      required: true
    }
  },
  // 组件状态值
  data () {
    return {
      article: {}, // 文章详情
      loading: true, // 加载的状态
      errStatus: 0, // 失败的状态码
      followLoading: false,
      totalCommentCount: 0, // 文章评论
      isPostShow: false, // 评论组件显示隐藏
      commentList: [],
      isReplyShow: false, // 评论回复组件展示隐藏
      currentComment: {} // 点击回复的那个评论对象
    }
  },
  // 计算属性
  computed: {},
  // 侦听器
  watch: {},
  // 生命周期钩子   注：没用到的钩子请自行删除
  /**
  * 组件实例创建完成，属性已绑定，但DOM还未生成，el属性还不存在
  */
  created () {
    this.loadArticle()
  },
  /**
  * el 被新创建的 vm.el 替换，并挂载到实例上去之后调用该钩子。
  * 如果 root 实例挂载了一个文档内元素，当 mounted 被调用时 vm.el 也在文档内。
  */
  mounted () {},
  // 组件方法
  methods: {
    async loadArticle () {
      // 展示加载状态
      this.loading = true
      try {
        const { data } = await getArticleById(this.articleId)
        // console.log(data)
        // 讲获取到的数据存到article中
        this.article = data.data

        // 初始化图片预览
        setTimeout(() => {
          // console.log(this.$refs['article-content'])
          this.previewImage()
        }, 0)
      } catch (err) {
        // console.log('获取信息失败', err)
        if (err.response && err.response.status === 404) {
          this.errStatus = 404
        }
        console.log('请求出错', 404)
      }
      // 关闭loading
      this.loading = false
    },
    previewImage () {
      // 封装一个方法
      // 得到所有的img节点
      const articleContent = this.$refs['article-content']
      const imgs = articleContent.querySelectorAll('img')
      // 获取所有 img 地址
      const images = []
      imgs.forEach((img, index) => {
        images.push(img.src)
        // 给每个 img 注册点击事件，在处理函数中调用预览
        img.onclick = () => {
          ImagePreview({
            images,
            // 预览图片的起始位置
            startPosition: index
          })
        }
      })
    },
    onPostSuccess (data) {
    // 关闭发布评论弹层
      this.isPostShow = false
      // 发布评论
      this.commentList.unshift(data.new_obj)
    },
    onReplyClick (comment) {
      // 将子组件中传给我评论对象存储到当前组件
      this.currentComment = comment
      this.isReplyShow = true
    }
  }
}
</script>

<style scoped lang="less">
@import './github-markdown.css';
.article-container {
  .main-wrap {
    position: fixed;
    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
    background-color: #fff;
  }
  .article-detail {
    position: fixed;
    left: 0;
    right: 0;
    top: 92px;
    bottom: 88px;
    overflow-y: scroll;
    background-color: #fff;
    .article-title {
      font-size: 40px;
      padding: 50px 32px;
      margin: 0;
      color: #3a3a3a;
    }

    .user-info {
      padding: 0 32px;
      .avatar {
        width: 70px;
        height: 70px;
        margin-right: 17px;
      }
      .van-cell__label {
        margin-top: 0;
      }
      .user-name {
        font-size: 24px;
        color: #3a3a3a;
      }
      .publish-date {
        font-size: 23px;
        color: #b7b7b7;
      }
      .follow-btn {
        width: 170px;
        height: 58px;
      }
    }

    .article-content {
      padding: 55px 32px;
      /deep/ p {
        text-align: justify;
      }
    }
  }

  .loading-wrap {
    padding: 200px 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #fff;
  }

  .error-wrap {
    padding: 200px 32px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: #fff;
    .van-icon {
      font-size: 122px;
      color: #b4b4b4;
    }
    .text {
      font-size: 30px;
      color: #666666;
      margin: 33px 0 46px;
    }
    .retry-btn {
      width: 280px;
      height: 70px;
      line-height: 70px;
      border: 1px solid #c3c3c3;
      font-size: 30px;
      color: #666666;
    }
  }

  .article-bottom {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    justify-content: space-around;
    align-items: center;
    box-sizing: border-box;
    height: 88px;
    border-top: 1px solid #d8d8d8;
    background-color: #fff;
    .comment-btn {
      width: 282px;
      height: 46px;
      border: 2px solid #eeeeee;
      font-size: 30px;
      line-height: 46px;
      color: #a7a7a7;
    }
    /deep/ .van-icon {
      font-size: 40px;
    }
    .comment-icon {
      top: 2px;
      color: #777;
      .van-info {
        font-size: 16px;
        background-color: #e22829;
      }
    }
    .btn-item {
      border: none;
      padding: 0;
      height: 40px;
      line-height: 40px;
      color: #777777;
    }
    .collect-btn--collected {
      color: #ffa500;
    }
    .like-btn--liked {
      color: #e5645f;
    }
  }
}
</style>
